The present invention relates to using organo-fluoro products comprising an amine or aminoalcohol function and a polyfluorinated chain as friction- and wear-reducing additives, and more particularly, it relates to the use of amino compounds with a polyfluorinated chain as soluble additives in lubricating oils in conjunction with conventional detergent/dispersant additives included in compounded oils for gasoline and diesel engines.
The use of certain organo-fluoro derivatives as additives in lubricant compositions is known. For instance, the use of salts of aliphatic amines and perhalogenated monocarboxylic acids is described in U.S. Pat. No. 3,565,926. Also, the use of derivatives obtained by reacting an aromatic amine and a fluorinated organic compound selected from the fluorinated saturated carboxylic monoacids or the fluorinated monocarboxylic acid chlorides is disclosed in French Patent No. 2,026,493. However, these carboxylic derivatives have the disadvantage of losing their anti-wear properties in the presence of ordinary additives such as dispersant/detergent additives, either as a result of physico-chemical interactions which impede their absorption by the surfaces which are to be lubricated or as a result of chemical interactions, particularly when the dispersant/detergent additives are neutral or superbasic alkaline earth metal salts. To the same effect, the publication of Kapsa et al, ASME Trans. 103, 486-496 (1981) mentions the harmful interaction of zinc dialkyldithiophosphates with conventional dispersant/detergent additives consisting of superbasic calcium sulfonates.